UMTS/HSPA(+) Module Series
UC200T-EM Hardware Design
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PWRKEY
4.7K
47K
10nF
Turn-on pulse
Figure 6: Turn on the Module Using Driving Circuit
The other way to control the PWRKEY is using a button directly. When pressing the key, electrostatic
strike may generate from finger. Therefore, a TVS component is indispensable to be placed nearby the
button for ESD protection. A reference circuit is shown in the following figure.
PWRKEY
S1
Close to S1
TVS
Figure 7: Turn on the Module Using Keystroke
3.6.2.
Turn off Module
The following procedures can be used to turn off the module:
⚫
Normal power down procedure: Turn off the module using the PWRKEY pin.
⚫
Normal power down procedure: Turn off the module using
AT+QPOWD
command.
3.6.2.1. Turn off Module Using the PWRKEY Pin
Driving the PWRKEY pin to a low level voltage, the module will execute power-down procedure after the
PWRKEY is released.